1. Field of the Invention
The present invention relates to clamp effort intensifiers for machine vises.
2. Prior Art
Machine vises of course have been quite well known in the prior art. For example, U.S. Pat. No. 3,397,880 shows a typical vise of the type disclosed herein, but without the clamp force intensifying device.
Additionally, U.S. Pat. No. 4,043,547 illustrates a machine vise having a movable jaw. The jaw has two parts. A belleville type spring washer is provided between the parts so that one of the parts of the movable jaw is kept from free movement under a small spring force even when there is no workpiece being clamped, but when a workpiece is clamped, the spring force is increased up to a relatively light load which holds the workpiece under a small clamping force. When large clamping forces are desired, the two portions of the movable jaw directly mechanically engage and the spring that is utilized is eliminated from the arrangement.
It should be noted that both of the above mentioned prior art patents show construction wherein the movable jaw will lock on a workpiece because the force from the nut that transmits motion to the movable jaw exerts the force of the movable jaw with a component that urges the jaw toward the ways supporting the movable jaw to clamp tightly. The same advantages can be incorporated with the vise of the present invention.
A further showing of a vise of the general type used herein is in U.S. Pat. No. 4,098,500.